A solenoid valve of this type, in which the connection passage between a pressure source and a user, for instance a hydraulic press connected to the pressure source, can be blocked or freed, is disclosed in German Offenlegungsschrift No. 35 28 296. In solenoid valves of this type, the traditional valve seat against which the valve member presses in its closed setting is a mechanical hard stop. The absolute seal of the valve is guaranteed only when this hard stop setting has been attained.
Security considerations require unequivocal control of the closed valve setting. Since the valve member moves only a few millimeters from its open setting into its closed setting or vice versa, forming either the completely closed or the completely open or free state of the connection passage requires maintaining a high level of precision in the measurements made for certain detection of the switch setting of the valve member on an electronic passage control device directly controlling the valve member.
Thus, the realization of reliable control of the valve member by means of electronic structural components has not been executable up until this time.